Flow State Aware QoS Management Without User Signalling

Abstract

Conventional packet network nodes react to congestion in the packet network by dropping packets in a manner which is perceived by users to be indiscriminate. In embodiments of the present invention, indiscriminate packet discards are prevented by causing packets to be discarded according to bandwidth allocations that intelligently track flow sending rates. Flows are allocated bandwidth based on policy information. Where such policy information indicates that the flow should be treated as delay-sensitive, the present invention includes means to allocate an initial minimum rate that will be guaranteed and such flows will also have the use of an additional capacity that varies depending on the number of such flows that currently share an available pool of capacity. This provides a congestion alleviation method which is less annoying to users since communications that have been in existence for longer are less susceptible to component packets being deleted.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims the benefit of priority to U.S. Provisional Application No. 61 / 118,964, filed on Dec. 1, 2008, titled “FLOW STATE AWARE QoS MANAGEMENT WITHOUT USER SIGNALLING” which is herein incorporated by reference in its entirety.DESCRIPTION OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to a communications network and a method of operating a communications network.[0004]2. Description of Background Art[0005]Recently, the demand for streaming video to a computer via the Internet has grown strongly. This has led to a need to supply increasing amounts of video material over local communication networks (whether the copper pairs used by telephone network operators or the coaxial cables used by cable television network operators).[0006]In telephony networks this additional demand is being met by the introduction of Digital Subscriber Loop (DSL) technology. As its name suggests, this technology c...

AI Technical Summary

Benefits of technology

[0096]This has the advantage of providing another gradation in the increase of quality of service offered to a communication with the age of the communication.

Problems solved by technology

Although such schemes prevent congestion, QoS management must also manage so-called “elastic” traffic where there is potentially a need for a minimum guaranteed rate but frequently a desire to transmit the flow as fast as possible, subject to network congestion constraints and constraints on maximum sending rates.

These schemes allow users access to communications resources but attempt to cause senders to decrease their sending rate on the onset of congestion.

This is unsuitable for video flows however, since real-time video servers cannot reduce their sending rate.

In most flow control schemes, all users are adversely affected by the onset of congestion.

The current deployment of flow base control, however, is limited only at the edge of the network.

However, flow level traffic control only at the edge cannot guarantee the flow level QoS.

On the other hand, having scalable control architecture for flow level traffic control along the data path is a challenging issue, because the number of flows in a network is huge.

However, the two approaches have outstanding issues.

As mentioned earlier, FAN is not designed for supporting various QoS requirement of the service.

This may stabilize the transport network in general, but the network provider cannot generate additional profit, because FAN cannot support the service that has special QoS treatment.

Enabling the signalling function in the terminal may cause the security hole in the network.

Second, this proposal focuses flow-based control in the access network, not the core.

In the core, the number of flows is high and call by call flow level control in RACF is difficult to achieve.

However, none of the above proposals provides a method of managing contention in a packet network which allows flow-based QoS mechanisms to offer:

Images